Methods and systems for improving the operation of transmissions for motor vehicles

ABSTRACT

A torque converter check valve has a valve element movable between a closed position and an open position by applying hydraulic pressure to a portion of the valve element and by applying a resilient force by a resilient element acting on another portion of the valve element. A spacer element is provided to act on the valve element and limit movement of the valve element in the direction in which the resilient element is compressed to reduce wear on the resilient element during operation of the torque converter check valve.

BACKGROUND OF THE INVENTION

The methods and systems of the present invention are directed to themodification and improvement of transmissions for automotive vehicles,more commonly referred to as “factory installed” transmissions,installed in automotive vehicles by an original motor vehiclemanufacturer. The invention is more particularly directed toimprovements to “factory installed” transmissions for the four speed98-04 Honda Odyssey, the five speed 98-04 Honda Odyssey, and the Acura3.2 TL.

The present inventor owns the following United States patents, thedisclosures of which are expressly incorporated by reference into thepresent patent application: U.S. Pat. No. 4,449,426, issued May 26,1984; U.S. Pat. No. 4,711,140, issued Dec. 8, 1987; U.S. Pat. No.4,790,938, issued Dec. 13, 1988; U.S. Pat. No. 5,253,549; issued Oct.19, 1993; U.S. Pat. No. 5,540,628, issued Jul. 30, 1996; U.S. Pat. No.5,624,342; issued Apr. 29, 1997; U.S. Pat. No. 5,730,685, issued Mar.24, 1998; U.S. Pat. No. 5,743,823, issued Apr. 28, 1998; U.S. Pat. No.5,768,953, issued Jun. 23, 1998; U.S. Pat. No. 5,820,507, issued Oct. 7,1998; U.S. Pat. No. 5,967,928, issued Oct. 19, 1999; U.S. Pat. No.6,099,429, issued Aug. 8, 2000; U.S. Pat. No. 6,117,047, issued Sep. 12,2000; U.S. Pat. No. 6,287,231, issued Sep. 11, 2001; U.S. Pat. No.6,390,944, issued May 21, 2002; U.S. Pat. No. 6,565,472, issued May 20,2003; U.S. Pat. No. 6,699,157, issued Mar. 2, 2004; U.S. Pat. No.6,729,989, issued May 4, 2004; U.S. Pat. No. 6,814,680, issued Nov. 9,2004; U.S. Pat. No. 6,871,397, issued Mar. 29, 2005; U.S. Pat. No.6,913,554, issued Jul. 5, 2005; U.S. Pat. No. 6,964,628, issued Nov. 15,2005; U.S. Pat. No. 7,128,679, issued Oct. 31, 2006; and U.S. Pat. No.7,331,893, issued Feb. 19, 2008.

It is the primary object of the present invention to modify the “factoryinstalled” transmissions for the 4 and 5 speed 98-04 Honda Odyssey andthe Acura 3.2TL transmissions to improve the overall operation andefficiency of these “factor installed” automotive transmissions. Themodifications to the “factory installed” transmissions, as more fullydescribed herein, include modification of the torque converter chargecircuit to adjust the valve stroke to prevent damage to a check valvespring as a result of high fluid pressure which can result in a torqueconverter overheat condition.

Other objects and advantages of the modification to the “factoryinstalled” automotive transmissions in accordance with the presentinvention will become apparent from the following description inconjunction with the drawings.

SUMMARY OF THE INVENTION

The primary object of the present invention is to protect the torqueconverter of a “factory installed” automotive transmission from damageresulting from over-pressurization. A hydraulic circuit of theautomotive transmission is coupled to a converter charge circuit. Whenpressure exceeds a predetermined value established by a torque converterlimit valve in the hydraulic circuit, a valve strokes towards a checkvalve spring to compress the spring and open the valve, resulting inventing of excessive converter pressure into a separate circuit coupledto pump suction. Over time, normal converter check valve activityweakens the check valve spring, causing it to malfunction or prematurelyrupture, resulting in loss of converter charge pressure, resulting insevere and damaging overheating of the torque converter.

In accordance with the present invention, a spacer element is arrangedto act on the valve element to limit the valve stroke, thereby limitingthe compressive forces applied to the spring as the valve moves into anopen position. The spacer element, by limiting the compressive forcesapplied to the check valve spring, reduce the wear on the spring,thereby preventing premature breakage of the spring and preventing lossof converter charge pressure which would otherwise result in severeoverheating of the torque converter.

It is also within the scope of the present invention to limit movementof the valve element as the valve element moves into a closed positionto limit the expansive forces applied to the spring.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates, in part, the hydraulic circuitry of a “factoryinstalled” automotive transmission for a motor vehicle;

FIG. 2 illustrates a portion of the hydraulic circuitry of theautomotive transmission illustrated by FIG. 1, showing the torqueconverter check valve in a closed position;

FIG. 3 illustrates the portion of the hydraulic circuitry illustrated byFIG. 2, showing the torque converter check valve in an open position;and

FIG. 4 illustrates the portion of the hydraulic circuitry illustrated byFIG. 3, as modified in accordance with the present invention.

DESCRIPTION OF THE BEST MODES FOR CARRYING OUT THE INVENTION

FIG. 1 of the drawing illustrates a portion of the overall hydrauliccircuitry of a “factory installed” automotive transmission for a 4 and 5speed 98-04 Honda Odyssey, and for the Acura 3.2 TL. The overallhydraulic circuitry of these “factory installed” automotivetransmissions is known to, and understood by, persons skilled in therelevant art.

FIG. 2 of the drawing illustrates a portion of the hydraulic circuitryillustrated by FIG. 1, isolating the torque converter check valve, whichis generally designated by reference numeral 2 in FIG. 2. In FIG. 2 ofthe drawing, the torque converter check valve is illustrated as being inits fully closed position. The torque converter check valve includes avalve element designated by reference numeral 4, a check valve springdesignated by reference numeral 6, a fluid flow line designated byreference numeral 8, and a fluid flow line designated by referencenumeral 10. In the closed position of the torque converter check valve2, the valve element 4 is in its uppermost position, blocking incominghydraulic fluid from a torque converter charge circuit through line 8.The valve element 4 is maintained in its uppermost position as a resultof the resilient force of the check valve spring 6, in its expandedstate, acting on the inside of the valve element 4. When the torqueconverter check valve is in its closed position as illustrated by FIG.2, hydraulic fluid flows through line 10 as a result of suction createdby a pump (not shown) coupled to line 10. The hydraulic pressure appliedto the outside of the valve element 4 through the line 8 is less thanthe resilient force of the spring 6 applied to the inside of the valveelement 4 to maintain the torque converter check valve in its closedposition, as illustrated by

FIG. 2. When the hydraulic pressure applied to the outside of the valveelement 4 during a downstroke (movement of the valve element from theclosed position into the open position), excess hydraulic pressure isvented by the suction in line 10 which is coupled to a suction pump(FIG. 3 of the drawing).

FIG. 3 illustrates the torque converter check valve shown in FIG. 2,when the valve is moved into its fully opened position. This occurs whenthe pressure of the hydraulic fluid applied to the outside of the valveelement 4 through the line 8 exceeds the resilient force applied by thecheck valve spring 6 against the inside of the valve element 4. In thefully opened position of the torque converter check valve as shown byFIG. 3, the valve element 4 has moved into its lowermost position, andthe check valve spring is in its most compressed position. Thus, whenthe valve element 4 moves in a downward stroke from its maximum upperposition when the torque converter check valve is fully closed (FIG. 2)into its maximum lower position when the torque converter check valve isfully opened (FIG. 3), the check valve spring 6 moves from a fullyexpanded state into a fully compressed state.

As the result of the continuous expansion and contraction of the checkvalve spring 6 during normal operation of the automotive transmission,the spring becomes weakened and subject to premature breakage. Failureof the check valve spring results in loss of the converter chargepressure from line 8, causing severe overheating of the torqueconverter.

FIG. 4 of the drawing illustrates a modification to the “factoryinstalled” automotive transmissions in accordance with the presentinvention. A spacer element designated by reference numeral 12 isprovided to act on the inside of the valve element 4 during the downstroke of the valve element 4 as it moves from its closed position toits opened position. Preferably, the spacer element is mounted to theproximate center of the inside of the top surface of the valve element,and extends longitudinally downwardly therefrom. As illustrated by FIG.4, the spacer element 12 prevents the valve element 4 from moving intoits maximum downward position (as illustrated by FIG. 3) when the torqueconverter check valve is in its fully opened position. Preferably, thespacer element is arranged within the spring which also acts on theinside of the top surface of the valve element. In this manner, thecheck valve spring 6 is not fully compressed when the torque convertercheck valve in its fully open position as illustrated FIG. 4. As such,the wear on the check valve spring is reduced during normal operation ofthe automotive transmission as the check valve spring is moved from itsmaximum expanded state into its modified maximum compressed state as aresult of the spacer element 12 which limits the downward stroke of thevalve element 4. The life of the check valve spring is increased, whilethe possibility of premature failure of the check valve spring isreduced, thereby preventing or reducing the possibility of loss ofconverter charge pressure and the resultant overheating of the torqueconverter.

The spacer element can be formed from any suitable material, such as alightweight durable metal or metal alloy.

In addition to employing the stroke limit spacer 12 to reduce the stressand wear of the check valve spring, the present invention also employs amore durable check valve spring then currently employed in the “factoryinstalled” automotive transmissions. In the preferred embodiment of thepresent invention, the check valve spring is a chrome silicon wirespring. Accordingly, the use of a more durable check valve spring incombination with the use of a stroke limiting spacer in accordance withthe preferred embodiment of the present invention, extends the operatinglife of the check valve spring, reducing the possibility of loss ofconverter charge pressure and the resulting overheating of the torqueconverter which would otherwise be caused by premature failure of thecheck valve spring.

As disclosed and illustrated herein, in the preferred embodiment of theinvention the spacer element is arranged so as to limit movement of thevalve element on its downstroke as the torque converter check valvemoves between a fully closed position and a fully opened position, tolimit the degree of compression of the check valve spring. It is alsowithin the scope of the present invention to reverse this arrangement sothat the spacer element is arranged to act on the outside of the topsurface of the valve element and limit movement of the valve element onits upstroke as the torque converter check valve moves from the openposition (FIG. 3) to the closed position (FIG. 2) to reduce the degreeof expansion of the check valve spring. In either embodiment of theinvention, wear of the check valve spring is reduced by reducing eitherthe compression or expansion of the check valve spring as the valveelement moves between closed and opened positions.

Other improvements and advantages within the scope of the presentinvention will be apparent to persons skilled in the relevant art.Accordingly, the description of the preferred embodiments of theinvention made herein are intended to be illustrative only, and notrestrictive of the scope of the invention, that scope being defined bythe following claims and all equivalents thereto.

1. A method of modifying an automotive transmission including a torqueconverter check valve having a valve element movable between a fullyclosed position and a fully opened position as a result of hydraulicpressure applied to said valve element to move said valve element in afirst direction, and a resilient element applying a resilient force onsaid valve element to move said valve element in a second direction, thesteps of said method including: providing a spacer element acting onsaid valve element for limiting the movement of said valve element inone of said first and second directions.
 2. The method in accordancewith claim 1, further including the step of arranging said spacerelement to limit movement of the valve element in a direction in whichsaid resilient element is compressed.
 3. The method in accordance withclaim 2, further including the step of applying the hydraulic pressureto the valve element so as to move the valve element in the directionwhich compresses the resilient element.
 4. The method in accordance withclaim 1, wherein said hydraulic pressure acts on said valve element tomove said valve element in said first direction from a closed positiontowards an opened position, and said resilient element acts on saidvalve element in said second direction to move said valve element froman opened position towards a closed position, the steps of said methodfurther including: arranging said spacer element to limit the distancewhich said valve element moves between a fully closed position and afully open position.
 5. The method in accordance with claim 1, furtherincluding the step of: arranging said resilient element to apply saidresilient force on the inside of said valve element.
 6. The method inaccordance with claim 1, further including the step of: applying saidhydraulic pressure to the outside of said valve element.
 7. The methodin accordance with claim 1, wherein said resilient element is a spring.8. A torque converter check valve for an automotive transmission, saidtorque converter check valve including a valve element, a resilientelement acting on said valve element to move said valve element in afirst direction, and means for applying hydraulic pressure to said valveelement for moving said valve element in a second direction, saidresilient element being expanded when said valve element moves in saidfirst direction, and said resilient element being compressed when saidvalve element moves in said second direction, and a spacer elementcooperating with said valve element for limiting movement of said valveelement in one of said first and second directions.
 9. The torqueconverter check valve in accordance with claim 8, wherein spacer elementis arranged to limit movement of the valve element in the seconddirection to limit the compression of the resilient element when thevalve element is moved in the second direction.
 10. The torque convertercheck valve as claimed in claim 8, wherein movement of the valve elementin the first direction closes the torque converter check valve.
 11. Thetorque converter check valve as claimed in claim 8, wherein movement ofthe valve element in the second direction opens the torque convertercheck valve.
 12. The torque converter check valve as claimed in claim 8,wherein said means for applying the hydraulic pressure to the valveelement is arranged to apply the hydraulic pressure to the outside ofthe valve element for moving the valve element in said second directionfor opening the torque converter check valve.
 13. The torque convertercheck valve as claimed in claim 8, wherein said resilient element isarranged to apply a resilient force on the inside of said valve elementfor moving the valve element in said first direction for closing thetorque converter check valve.
 14. The torque converter check valve inaccordance with claim 9, wherein said spacer element is arranged tolimit the distance that said valve element moves in said seconddirection from a closed position into an opened position.
 15. The torqueconverter check valve in accordance with claim 14, wherein said spacerelement is arranged to cooperate with the inside of said valve element.16. The torque converter check valve in accordance with claim 15,wherein said resilient element is arranged to act on the inside of saidvalve element, and said spacer element is arranged inside of saidresilient element.
 17. The torque converter check valve in accordancewith claim 8, wherein said resilient element is a chrome silicon wirespring.
 18. A torque converter check valve for an automotivetransmission, said torque converter check valve including a valveelement, a resilient element acting on said valve element for movingsaid valve element between a fully opened position and a fully closedposition, means for applying hydraulic pressure to said valve elementfor moving said valve element from a fully closed position to a fullyopened position, said hydraulic pressure applied to said valve elementexceeding said resilient force applied to said valve element when saidvalve element is moved from said fully closed position into said fullyopened position wherein said resilient element is compressed when saidvalve element is moved from said fully closed position into said fullyopened position, a spacer element cooperating with said valve elementfor limiting the distance travel by said valve element when said valveelement is moved from said fully opened position to said fully closedposition, wherein said spacer element reduces the degree to which saidresilient element is compressed in said fully opened position of saidvalve element.
 19. The torque converter check valve in accordance withclaim 19, wherein both said spacer element and said resilient elementare arranged to act on the inside of said valve element.
 20. The torqueconverter check valve in accordance with claim 19, wherein said spacerelement is arranged within said resilient element.